Breast-feeding mothers need 2000 IU of vitamin D to get infants to even 12 ng
Maternal vitamin D3 supplementation at 50 μg/d protects against low serum 25-hydroxyvitamin D in infants at 8 wk of age: a randomized controlled trial of 3 doses of vitamin D beginning in gestation and continued in lactation1
Kaitlin M March2, Nancy N Chen2, Crystal D Karakochuk2, Antonia W Shand5, Sheila M Innis3, Peter von Dadelszen4, Susan I Barr2, Michael R Lyon6, Susan J Whiting7, Hope A Weiler8, and Tim J Green2, tim.green@ubc.ca
2Food, Nutrition and Health,
3Department of Paediatrics, and
4Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, Canada;
5Clinical and Population Perinatal Health Research, Kolling Institute, University of Sydney, Sydney, Australia;
6Canadian Center for Functional Medicine, Coquitlam, Canada;
7College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Canada; and
8School of Dietetics and Human Nutrition, McGill University, Montréal, Canada
↵1 Supported by the Canadian Institutes for Health Research (CIHR) and a Frederick Banting and Charles Best Canada Graduate Scholarship from the CIHR (KMM). Supplements were provided by Natural Factors (Coquitlam, Canada). Natural Factors had no role in the study design, implementation, or interpretation of the study findings.
Background: Vitamin D supplementation is recommended for breastfed infants. Maternal supplementation beginning in gestation is a potential alternative, but its efficacy in maintaining infant 25-hydroxyvitamin D [25(OH)D] concentration after birth is unknown.
Objectives: We determined the effect of 3 doses of maternal vitamin D supplementation beginning in gestation and continued in lactation on infant serum 25(OH)D and compared the prevalence of infant serum 25(OH)D cutoffs (>30, >40, >50, and >75 nmol/L) by dose at 8 wk of age.
Design: Pregnant women (n = 226) were randomly allocated to receive 10, 25, or 50 μg vitamin D3/d from 13 to 24 wk of gestation until 8 wk postpartum, with no infant supplementation. Mother and infant blood was collected at 8 wk postpartum.
Results: At 8 wk postpartum, mean [nmol/L (95% CI)] infant 25(OH)D at 8 wk was higher in the 50-μg/d [75 (67, 83)] than in the 25-μg/d [52 (45, 58)] or 10-μg/d [45 (38, 52)] vitamin D groups (P < 0.05). Fewer infants born to mothers in the 50-μg/d group had a 25(OH)D concentration <30 nmol/L (indicative of deficiency) than infants in the 25- and 10-μg/d groups, respectively (2% vs. 16% and 43%; P < 0.05). Fewer than 15% of infants in the 10- or 25-μg/d groups achieved a 25(OH)D concentration >75 nmol/L compared with 44% in the 50-μg/d group (P < 0.05). Almost all infants (∼98%, n = 44) born to mothers in the 50-μg/d group achieved a 25(OH)D concentration >30 nmol/L. At 8 wk postpartum, mean [nmol/L (95% CI)] maternal 25(OH)D concentration was higher in the 50-μg/d [88 (84, 91)] than in the 25-μg/d [78 (74, 81)] or 10-μg/d [69 (66, 73)] groups (P < 0.05).
Conclusions: Maternal supplementation beginning in gestation with 50 μg vitamin D3/d protects 98% of unsupplemented breastfed infants against 25(OH)D deficiency (<30 nmol/L) to at least 8 wk, whereas 10 or 25 μg vitamin D/d protects only 57% and 84% of infants, respectively. This trial was registered at clinicaltrials.gov as NCT01112891.